Monoazo dye for lakes.



} KARL SCHLNITZSPAHN, 0F OFFENBACH-ON-THE-MAIN, GERMANY, ASSIGNOR TO COR- PORATIQH tl-F CHEMISCHE FABRIK GRIESHEIM ELEKTRON AT FRANKFORT-ON- THE-LEEAUI, GERMANY.

MONQAZO DYE FOR LAKES.

He Drawing.

Specification of Letters Pateiit. P t t d 22, 1 Application filed July 13, 1910. Serial No. 571,698.

To all whom it may concern:

Be itlrnown that I, KARL SOHNITZSPAHN,

doctor of philosophy, chemist, a subject of the German Emperor, and resident of Often bach-on-the-Main, in the Grand Duchy of Hesse, Germany, with the post-office address Obermainstrasse No. 81, have invented new and Useful Improvements in a Monoazo Dyefor Lakes, of which the following is a,

trate the nature of my invention. The parts are by Weight: 52,2 parts of the sodium salt of Q-naphthylanun- :8-disulfonic acid are dissolved in 500 parts of water. Thissolutionis cooled by addition of ice, 10,35 parts of sodium nitrite are added and the solution is poured in diluted hydrochloric acid, which corresponds to 67 parts of hydrochloric acid 2& Baum." The diazo compound thus obtained is then poured into a cold solution of parts of 2.3-oxynaphthoic acid in 700 parts of water and 30 parts of caustic soda lye Baum and mixed with 53 parts of sodium' carbonate. After the combination is completed the mass is heated and the dyestufl' is precipitated by addition of common salt. It

July 1910.-

forms in dry state a red-brown powder and 1s soluble in concentrated sulfuric acid with very bluishred color, in water with yellowish-red color. .This solution is changed both by addition of caustic soda lye and by addit1on of hydrochloric acid in a bluish-red color.

The dyestuif is changed into the pigment colors in usual manner. The preparation of the dyestulf and the formation of the lake can be obtained naturally in one operation in usual methods.

Now whatI claim and desire to secure by Letters Patent,- is the following:

1. The prclss for the production of a monoazodyesttgfgspecially. valuable for pre-- paring pigmen colors consisting in the combination of the diazo compound of 2-naphthylamin-4: 8-disulfonic acid with 2.3-oxynaphthoic acid. a

2. As a new article, the dyestufi' obtained by the combination of the diazo compound of 2-naphthyla'min-4e8-disulfonic acid with 2.3-oxynaphthoic acid, which dyestuif forms in dry state a red-brown powder and is soluble in concentrated sulfuric acid with very bluish-red color and in water with yellowish-red color; the solution being changed both by addition of caustic soda lye and by addition of hydrochloric acld to a bluish-red color and the dyestuif capable of being transformed into very bluish-red pigment colors.

In testimony, that I claim the foregoing as my invention, I have signed my name in presence of two witnesses, this first day of KARL SOliNITZSPAHN.

I Witnesses:

KATHINKA PFEIFFER, HERMANN WERT. 

